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UNITED ST PATEN'I ()FFICE ED\VIN J. WATSON AND CHARLES- S. HALL, OF \VORCESTER, MASS.

PROCESS OF MANUFACTURING WIRE.

SPECIFICATION forming part of Letters Patent No. 279,295, dated June 12,1883,

Application filed May 4, 1852. (No model.)

To all whom it may concern:

Be it known that we, EDWIN J. \VATSON and CHAS. S. HALL, both of the city and county of \Vorcester, and State of Massachusetts, have invented certain new and useful Improvements in the Method or Process of Manufacturing \V ire, of which improvements the following specification is a full description.

This invention has reference to the manufacture of wire by annealing and reducing by means of dies; and its object is to facilitate and improve the annealing and drawing of the wire and toeifect a saving of time and expense in the manufacture.

In the ordinary processes of annealing in an annealing potor muffle, the ,wire, being exposed hot to the atmosphere, has formed upon its surface a scale or coating of oxide of iron. If this scale were allowed to remain, it would in the process of drawing out and otherwise inj are the dies and interfere with their operation, and the wire produced would be of a very inferior quality. The removal of such scale before drawing the wire is therefore imperative, and it is commonly effected by treatment in an acid bath. This treatment, however, renders the wire brittle and necessitates frequent anneal ing to soften the wire duringthe drawing pro cess. It also necessitates other treatment such as bluingto remove the ill effects of the acid, in course of which the liability to the formation of a new scale is incurred. These frequent cleanings and reannealings render production of wire very tedious and costly. Then the annealing is performed, as is some times done, by immersing the wire rods or stock in a bath of melted lead, instead of a scale of oxide of iron being formed thereon, it becomes coated with a layer of lead oxide; but this has always been considered objectionable, and no matter what the nature of the crust formed incidental to the process of annealing, it has been the invariable practice heretofore to remove it, either by tfeatment with acids or by cleaning or scouring in some other way, before drawing the wire through dies.

Our invention consists in annealing the wire rods in melted lead, as above indicated, thus forming a layer of lead oxide thereon, and then wire-drawing without removing such layer, we having found that the presence of the coating of lead oxide, in connection with a coating of lime, flour, meal, or other known or suit-able lubricant, or anti-friction material, enables the wire to be more freely and easily drawn through dies, and with less frequent softening than has been possible under the processes in common use.

In order that our invention may be the bet ter understood by persons skilled in the artto which it relates, the manner in which the same is or may be carried into effect will now be described more in detail.

The wire rods or wire as taken off the reel in the rolling-mill are dipped in bulk in abath of melted lead, so as to be in direct contact with the fused metal therein. The heat of the bath and the length of continuance of the treatment will be varied, as well understood, ac cording to the nature of the material dealt with and the character-of final product desired. regulated to avoid overheating or imperfect annealing from insufficient heat. The stock under treatment in the bath can be quickly changed and heat economizcd by keeping the latter at or near the same temperature. hen the rods or wire are removed from the bath they are coated with lead oxide. This coating prevents scaling, and, moreover, by allowing it to remain on the wire in the process of drawing, that operation, instead of being hindered, will be greatly facilitated. Instead, therefore, of cleaning off the coating by acids or otherwise, as in the ordinary processes of manufacture, it is retained on the rods. These are next coated with lime, flour, meal, or other known or suitable lubricant or anti-friction coating, and four drafts may be drawn through the dies, reducing the wire to No. 12 without reannealing, we having found by experiment that the presence of the coating of lead oxide enables more drafts to be drawn without reannealing than could otherwise be done. The No. 12 wire is then reannealed, as before, in melted lead, a new coating of lead oxide being thus formed, and the wireagain coated with lime, flour, meal, or other lubricant, when may be drawn to No. 15.

It will be seen that by the newproccss of drawing wire the time of the operation is greatly shortened, and that it will enable manufacturers to largely increase their production.

The heat of the bath can be very nicely \Vith the presence of the coating of lead oxide, not only is the drawing through dies facilitated, but the wire produced is of an exceedingly fine quality, very strong, and uniform in texture.

A very great saving is effected by dispensing with the frequent cleanings in acid after annealing, which heretofore has ordinarily been necessary three or drawing of the wire. The acid treatment, moreover, affected the character of the wire itself, rendering it brittle and necessitating frequent reannealing. These objections and dificulties are also removed by the present improvement.

\Vhen the wires have become rusty, orhave been annealed otherwise than by the process indicated, or when for any other reason it has been necessary to clean them in acid, the treatment in a lead bath may be advantageously substituted for the ordinary process of bluing, or heating to about a blue heat to remove the effects of the acid.

\Ve have referred to melted lead solely in the foregoing description; but any other metal or metallic alloy which will accomplish the purposes may be usedas, for example, tin, of lead, sueh.

antimony, or alloys of the same or and our invention includes the use of more times during the contact with the melted metal, whereby a coating of lead oxide is formed on said wire rods, and drawing the same through dies with the coating of lead oxide thereon, substantially as described. r

2. The method of manufacturing wire by forming on the wire rods or stock a coating-of lead oxide, as by annealing in a bath of melted lead, then coating with. lime, flour, meal, or other anti-friction coating, and wiredrawing through dies, substantially as described.

lVi t nesses JOHN C. DEWEY, THos. H. DODGE. 

